Introduction
Cystic fibrosis is a hereditary disease, which attacks mainly the lungs. The disorder may also affect the liver, intestines, kidney, and pancreas. The long-term effects of the condition include lung infections, which result in a patient coughing up mucus and having challenges in breathing. According to Davis and Ferkol (2013), the disease attacks cells, which secrete sweat, mucus, and digestive juices. The fluids are usually slippery and thin. However, for individuals suffering from cystic fibrosis, a flawed gene leads to the fluids becoming thick and sticky. They block ducts, tubes, and passageways, particularly in the pancreases and lungs. Even though the condition demands daily care, individuals suffering from the disease can go to school and do their usual activities without challenges. Cystic fibrosis is incurable. Nevertheless, doctors use drugs to treat the affected organs. For instance, they use antibiotics to manage infected lungs. In the case the infection gets worse, the doctors may recommend lung transplantation as a last resort. In developed countries, individuals suffering from cystic fibrosis may live for up to between 42 and 50 years. Over 80% of deaths related to cystic fibrosis are a result of lung complications (Davis & Ferkol, 2013). Thus, this paper will discuss cystic fibrosis (CF) lung disease as a significant genetic disorder.
Etiology
Cystic fibrosis is a hereditary illness that results from changes in a gene called cystic fibrosis transmembrane conductance regulator (CFTR). Davis and Ferkol (2013) posit, “The inheritance is autosomal recessive” (p. 2027). For a person to be diagnosed with cystic fibrosis, he/she must possess two malfunctioning CFTR genes, which are inherited from both parents. Individuals with one CFTR mutation are regarded as carriers and do not show signs of cystic fibrosis. Davis and Ferkol (2013) argue that there are more than 1,800 forms of CFTR transmutations, which cause cystic fibrosis. The most predominant mutation is referred to as F508del-CFTR and comprises about 67% of all the mutations globally (Davis & Ferkol, 2013). A person with cystic fibrosis can either be homozygote or heterozygote. A homozygote is a patient with identical copies of CFTR mutation. On the other hand, a heterozygote patient has two different copies of CFTR mutation. Possession of identical copies of CFTR, especially F508del-CFTR is linked to severe cystic fibrosis.
Pathogenesis
As aforementioned, cystic fibrosis affects different organs. Consequently, patients suffering from the condition show different symptoms depending on the affected organ. This study will focus on the pathogenesis of cystic fibrosis (CF) lung disease. Research shows that “chronic bacterial airway infection, prominent neutrophilic inflammation and mucus in airways, and progressive bronchiectasis characterize advanced CF lung disease, which causes most morbidity and death in people with the condition” (Cantin, Hartl, Konstan, & Chmiel, 2015, p. 421). Research shows that at least 33% of children who suffer from CF lung disease show signs of bronchiectasis as early as at the age of three. Pulmonary infection and inflammation are evident even before the symptoms manifest. Nevertheless, it is hard to tell which condition arises first. Cystic fibrosis centers have learned that CF lung disease appears long before symptoms become noticeable. Consequently, they have come up with mechanisms to facilitate early intervention.
Persons with CF go through successive phases of lung disease. Cantin et al. (2015) aver, “CF lung disease progression is heterogeneous, with the age at which an individual reaches a given stage indicating the relative aggressiveness of his/her disease phenotype” (p. 425). Medical examinations have shown that at the onset, patients with CF lung cancer suffer from chronic or sporadic infection of the respiratory tract. In the beginning, the patient suffered from bronchiectasis and mucinous plugging. Weakened mucociliary clearance and swelling resulted in the constant contagion of airways. At least a third of infants with the condition suffer from Staphylococcus aureus in the lower respiratory duct. Continued infection of the respiratory tube led to the patient displaying signs like the rise in the level of inflammatory mediators, wheezing, and high air trapping.
Failure to treat CF lung disease at an early stage contributed to its progression. At the teenage, the patient showed signs of persistent pulmonary illness with P aeruginosa (Ciofu, Hansen, & Hoiby, 2013). The sickness is attributed to a more and brisk reduction in lung function. It also contributes to increased cases of deaths. According to Ciofu et al. (2013), P aeruginosa can cause chronic infection due to the development of biofilm on the damaged respiratory epithelium. The biofilm made it hard for the patient to treat the disease with antibiotics. It became increasingly hard for the patient to breath due to continued bacterial attack. Additionally, the patient showed severe respiratory symptoms known as pulmonary exacerbations (Bhatt, 2013). As per Bhatt (2013), pulmonary exacerbations may manifest at an early age. Even though children suffer incidences of exacerbation, the problem intensifies as one grows. By the age of 12, the patient suffered from a pulmonary exacerbation, at least once per year. At this stage, the patient required dietary and noninvasive ventilatory support to manage the disease. Additionally, they needed supplementary oxygen due to breathing challenges.
Studies show that a patient at the third stage of CF lung disease has less than 10s control pulse (CP), particularly in the morning hours (Bhatt, 2013). The patient’s blood was unable to control the spread of different infections, leading to their health deteriorating. Additionally, they showed numerous complications, which included pneumothorax and hemoptysis. They also complained of severe chest pain, dyspnea, and breathing problems. Severe aberrations in the CFTR function worsened the clinical picture of the condition.
Based on the current status of the patient, one can conclude that they are in the final phase of the disease. The illness has progressed insidiously to the present state. A study shows that an individual in the end-stage of the condition has less than 5s CP (Sly et al., 2013). Currently, the patient is on the verge of death, and only a lung transplant can help to save their life. Sly et al. (2013) assert, “Severe alveolar hyperventilation leads to critically low carbon dioxide levels in airways with frequent development of cor pulmonale (high blood pressure in the pulmonary arteries)” (p. 1965). Right heart overload, coupled with cor pulmonale are prevalent among patients in the final phase of CF lung disease and contributes to fatalities. Today, the patient is regularly admitted due to conditions attributed to high blood pressure and breathing complications.
Clinical Manifestation
A patient with CF lung disease shows different symptoms according to the stage of the illness. The condition is chronic and progresses subtly. At the age of 5, the patient showed mild symptoms of lung disease (Sly et al., 2013). They often suffered from persistent nasal polyposis. Additionally, the patient showed signs of infection in the gastrointestinal tract. The patient did not take the symptoms seriously. Thus, they did not seek early treatment to control the illness. At the age of 9, they started to show multiple biochemical and physiological defects (Sly et al., 2013). The immune system became weak, and they had challenges with protein metabolism. The infection of the airways resulted in mucociliary dysfunction and persistent inflammation. The patient showed symptoms linked to bronchitis. The deficiency of carbon dioxide in the airways (hypomania) led to them developing bronchoconstriction.
At the age of 17, the patient could complain of chest pain and shortness of breath whenever they engage in sports activities. They were referred to a chest physician who noted that the patient had subnormal lung function and nail clubbing. Continued attack of the respiratory system led to them suffering from bronchiectasis characterized by frequent pulmonary exacerbations (Sly et al., 2013). The patient developed various complications, among them pneumothorax, hemoptysis, and severe dyspnea.
The CF lung condition gets severe gradually over a couple of years. A patient shows numerous symptoms at the final phase of the illness. One of the most predominant symptoms is running out of breath (Sly et al., 2013). Breathing complications may develop gradually or rapidly. In this case, the patient claims that their breathing problem has progressively worsened over two months. The lungs do not regain their original function after each flare-up. Consequently, the patient experiences difficulties in breathing. The patient stated that physical exertions like eating, speaking, or adjusting position led to them feeling out of breath. Impaired lung function has contributed to a reduction in the level of oxygen in the patient’s blood. As a result, they are hospitalized due to congested liver and fluid accumulation in the tummy and legs.
The Affected Organ
The CF lung disease, as the name suggests, affects the lungs. The disease causes “abnormal mucus production along the respiratory tract due to the faulty transportation of electrolytes across airway tissues” (Stoltz, Meyerholz, & Welsh, 2015, p. 354). The mucus dries out fast, hence difficult to remove from the airway. The inability to clear the dry mucus results in the damage of the alveoli and constriction. It also facilitates the accumulation of foreign particles in the lungs, leading to infections. The blockage of the airways makes it hard for a patient to breathe because air cannot go through. Additionally, bacteria grow in the mucus collection, causing infections in the sinuses, nose, and lungs. Some patients may develop nasal polyps. According to Stoltz et al. (2015), CF lung disease causes constriction of arteries, resulting in high pressure in the lungs (pulmonary hypertension).
Lesion Distribution
CF lung disease affects the lobes of both lungs. Thus, the distribution of the disease is diffuse. Stoltz et al. (2015) define diffuse distribution as one that covers the entire lobes of the two lungs. Despite the CF lung disease being extensive, it does not necessarily affect all lung areas equally. An examination of chest radiography shows the presence of “multiple thin-walled, air-filled spaces in the pulmonary parenchyma” (Stoltz et al., 2015, p. 361). Images from computer tomography (CT) reveal the presence of cysts, which are distributed across the lungs. As the disease progresses, the lesions coalesce to form huge cystic airspaces.
Risk Factors
The sole risk factor for CF lung disease is being born of two parents with abnormal cystic fibrosis genes. As aforesaid, the condition is hereditary. Hence, one can inherit the abnormal genes from parents. Nonetheless, numerous factors influence the development of the disease. One of the elements is gene defects (Sanders et al., 2014). The condition may have developed due to the CF gene mutation. Defects in the CFTR gene may have contributed to the accumulation of thick and sticky mucus around the airways, facilitating bacterial infection. Lifestyle and environment may have also led to the development of the illness (Sanders et al., 2014). The inability of the patient to consume a sufficient amount of calories could have contributed to underweight and retarded growth. Additionally, the patient claims that they are not active physically. Failure to engage in physical activities may have resulted in the deteriorating health of the patient’s lungs (Sanders et al., 2014). The patient does not smoke. However, some of their siblings are smokers. Hence, exposure to secondary smoke could have worsened the disease. CF lung disease progresses with age. Therefore, age must have also contributed to the development of the illness.
Sequelae
Patients suffering from acute CF lung disease are at risk of contracting other illnesses like diabetes. Hoffman and Ramsey (2013) aver, “Due to greatly reduced oxygenation and increased risk of diabetes, patients with end-stage CF lung disease are also likely to be at greater risk for neurocognitive impairment” (p. 211). A study conducted on 18 patients suffering from end-stage CF lung disease found that they had neurocognitive impairments, particularly in noncontextual verbal (Hoffman & Ramsey, 2013). Moreover, most patients showed either instant or deferred free recall impairments. Some could take up to 30 minutes to remember things (Hoffman & Ramsey, 2013). Others had persistent long-term remembrance deficits. Over 30% of the patients had permanent storage deficits (Hoffman & Ramsey, 2013). Thus, the patient might develop neurocognitive challenges in the future.
Prognosis
CF lung disease is a genetic condition with no cure. Nevertheless, technological advancements in the medical field have made it easy to manage the illness (Sawicki et al., 2013). Indeed, the attitude of patients suffering from the condition has never been this optimistic. Five decades back, individuals with the condition could not live past infancy, and if lucky, school-age (Sawicki et al., 2013). Today, patients can live with the condition for over 40 years (Sawicki et al., 2013). The collaboration between scientists, clinical caregivers, and families has facilitated the formulation of universal best practices. Many new, valuable treatment procedures have emerged, making the life of patients with CF lung condition bearable.
Therapies
Despite the lack of a cure for CF lung condition, doctors administer different drugs to manage the disease. Patients with CF lung disease use different types of antibiotics regularly to prophylactically contain infection (Mogayzel et al., 2013). Mogayzel et al. (2013) allege that antibiotics are essential whenever a patient shows signs of declined lung function or suspects a possible pneumonia attack. Currently, research is underway to develop gene therapy as an alternative remedy for CF lung disease. The objective of the treatment is to restore defective CFTR DNA (Mogayzel et al., 2013). It will go a long way towards facilitating the generation of useful CFTR protein in epithelium cells.
Conclusion
The CF lung disease is a hereditary condition that arises due to defects in CFTR protein. The progression of the disease is atypical, thus making it hard for healthcare providers to come up with efficient methods of managing the condition. Even though the F508del mutation is the primary cause of CF lung disease, other numerous mutations can lead to the disease. The various mutations occur in diverse areas of the CFTR protein, leading to different molecular defects. If the CF lung condition is not managed, it can lead to death. Additionally, the patient may develop neurocognitive complications.
References
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